First Returns of Adult Sockeye Salmon from Hatchery-Reared Age (Underyearling) Smolts

The anadromous life history of Pacific salmon (Oncorhynchus spp.) is characterized by distinct fresh-water and saltwater phases -- with some species requiring longer periods of freshwater residency than others. The sockeye salmon (O. nerka) typically spends one or two growing seasons in nursery lakes before the fry smolt and migrate to the ocean. However, the species is also characterized by individuals from some stocks in certiIn environments which migrate naturally to sea as age-0 smolts. Because of the generalized requirement for a period of freshwater residency after the initial freshwater incubation period, enhancement methods for sockeye salmon in Alaska usually follow one of two strategies.

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